Automatic pressure-switch controller.



C. S. JENNINGS. AUTOMATIC PRESSURE SWITCH CONTROLLER.

APPLICATION FILED MAY 31,1907.

P"":nted J an. 13 19 14.

G, S. JENNINGS. AUTOMATIC PRESSURE SWITCH CONTROLLER. APPLICATION FILED MAY 31, 1907.

Patanted Jan. 13, m4.

2] SHBETSSHEET 2.

G. S. JENNINGS. AUTOMATIC PRESSURE swrrcu CONTROLLER.

APPLICATION FILED MAY 31, 1907.

Patentefi Jan. 13. 192.

3 EHBETB-SHEIZT 3.

wwaaasa:

- mm) sTA rps PA TENT OFFICE,

v CHESTER'S. JENNINGS, or BOSTD iMASSACHUSE'ITS, ASSIGNOR mana ements:

1 or NEWARK, new J 'BS'EY, AcoRroRA'rron or NEW JERSEY."

AUTOMATIC PRESSURE-SWITCH I CONTROLLER. L

TO-allwhom it may concern:

T QBe it gknown that I, CHEsrnR S. JEN- ion?" State of h'la ssachusetts have invented -cert;a1n -new and useful Improvements in Automatic Pressure-Switch Controllers of which the following is a specification.

pressur sure actua e -mechanism for operatingthe switch' controlling the motor driving the ances.

.erating' position.

pump and also to prevent violent fluctua-v -tions of the' pressure from acting suddenly on said switch;

In the accompanying drawings which illustrateaconstruction embodying my 1nvent-ion Figure 1 is a View illustrating one form-"o my invention. Fig. 2 is a diagram of electric; circuits hereinafter described. Fig. 3. "isan elevation partly in section of thef'rheostat "and cont-rolling mechanism showing the position of the parts when the 'systen ris' not in operation. Fig. 4 is a similar view -to Fig. 3 showing the parts in; op-

"Lik'e'letteils of reference refer. to like parts throughout "the several views.

The-apparatus as shown is adapted to operate "as to maintain a constant or predete edfvacuum in the drum Awhich is a res sup ly for numerous transmission tubes.1-,Thef-air is exhausted from the drum A by ablower o-r pump B driven by a .mo-

tor Gthr'ough a belt'c. I a

"s a rheostat for controlling themotor Cand E is a controller for the rheos't-at. Therhe'o'stat D-has two-contact ar'msti and d, the arm d cotiperating with. a seriesof contacts'zi while the'armd cooperates with a series'of contacts 0Z As shownin Fig. .2 the contacts d (5 are connected by resist- The two arms (Z d are plvoted on.

and electrically connected with one post (i invention relates toimprovements in Specification of Letters Patent. Application filed ma 31. 1907. Serial No. 376,581.

1 by .a valve o which is connected by wire (Z with a linewire d through the usual cut-out F. One end of. the series of contacts d is connected by a 1 wire (Z with one brush d of the armature I the vacuum in the drum A- and when the Patented Jar 1.113; 1 914:.

.of motor C and the other brush (Z of said motor s connected by a wire-(Z with theother line wire al through the'cut-out F.

The field 0 of motor C is a shunt including wire (1, d, 01, contacts (Z and arm (mm wire (Z which leads to the line wire (5. Thus the movement of arm d 'overcontacts (l and plate (1 which is connected by the wire (1 with the'field, circuit, varies the resistance in the armature of motor C and the moveirent of arm-d over contacts d varies the resistancein'thefieldof motor C. At G is the usual magnet forholdingthe arm d at its highest point where-the re- I sistance in the armature circuitfis at the minimum. One end ofthe Caner magnet G is connected by a wire gwith1the*-.wire (Z and the other end by the wire'g ifwithene end of a series of resistances d v is pivoted on the post (lj and is rnade with a handle (Z by means of which it is swung on said postto start and stop the motor. 1 4

Pivoted. on the pin d" and on top of the arm (Z is a lever (Z having'a slot d i into which The are d projects a pin (Z on the arm d; In this way, the arm d and lever e1 are'connected, w1th prov sion for linilted relative movement. The handle (Z also extends through a slot 1 to permit this relative movement.

Below t-hearm (Z is the am d cooperating with the contacts d as describedl Thetwo arms (Z and d are connected as usual vso that when the operator by means of theahanjdle d lifts'the armcl andlever (Z thearm di is lifted by the arm cl juntil the armd is caught'and retained by the magnet-G; when the latter is'deenergized the arm'd falls by gravity or through the. actionof aspring into its lowest positionlunder the armd.

The arm (Z is of insulatingmaterial and is normally engaged and adapted to be operated bya grooved r'oller df mounted on the upper end of a piston rod d flsaid lever. d

being normally held against saidyroll by ca spring (1. The rod (l isofixed to a piston Z in a cylinder (1 connected-at its .uppepend with pipe A'by a pipe 037*," at.-the lowcrend of the cylinder Iis ;-;port d openingto the'atmosphere whose .capacit yis. regulated H so that; rapid movement of piston (l in either direction, is prevented. The lower end of rod (1" carries weight (1 which acts as a counterbalance against system is not in operation holds the piston 1Z at the lower end of cylinder (W as shown in Figs, 1 and 8.

When the system is to -be started up'to create and maintain a normal working pres,- sure in the drum A, the operator starts the motor G by grasping the handle (Z and lifting the lever (Z arm (Z and arm (Z to their highest point. During their upward movement, the passage of the arms (Z and (Z over heirrespectivc contacts reduces the resistance inboth the armature and field circuits 'to the minimum. As the motor G operates the, blower B, the air in the drum A and in the cylinder a? above the piston (2 is exhausted and said piston is raised until the roll Z? engages the lever (Z .The operator then frees the handle (I and thereafter the lever (1. is supportedentirely by the roll al During-the use .of the system, the pressure in the pipe-or drum A fluctuates and there tore the piston (Z is raised and lowered, but as will now be obvious, the pin and slot connection d d? between the arm-(Z andlever d permits limited movementof the'lattez." independently of the arm d so that a change of pressure in drum Ato apredetermined extent must occur before arm d is moved by lever (2 'Wl1en such a change of pressure occurs, the end of the slot (2 engages the pin (Z andarm (Z is moved with the lever- (Z so as to vary the resistance in the-field, such variations occurring so as to speed up the motor O whcmthe pressure varies in one directionand to slowdown the motor when the pressure varies in the other direction. Thus it willobe' seen that comparative slight variationsfrom the normal or working pressure'in' the drum A do not affect the motor C while extended fluctuations in eithei'diree' tion actto regulate the speed ofthemotor' C to maintain the normal pressure. When the system is shut down,. the m'otoryG "is stopped by opening the switch or cnt out' -F" Whereupon the parts assume the non-openating position shown in Fig. 3.

Having thus described the nature. of my v invention and set forth a construction em-" bodylng the same, what I claim as new. and

desire torsecure. by LettersPatent'of't-he United States is:

v 1'. In an automatic pressure controller, the

combination of a drum, means for exhausting air from said-drum," a cylinder -communicating at its upper end with said drum and havingiat' its lower end a port; to the outside air, an adjust-able valve controlling said port, a piston in saidcylinder movable thereinthrough a difference in the pressures;

in the cylinder above and below; the piston, a rod carried by saidpiston pass ng through theupper and lower ends of said cylinder,

' two subscribing May, A; D. 1907.,

a friction roll .on the upper end of said: rod,

a hinged controller arm engaged by said,

roll and actuated by. the movement of said rod, and a counterweight on the lower end of aid 'rod to counterbalance the partial vacuum inthe bylinder above the piston.

chamber of variable sizeu'pon each side of" said partition, connections between one of said chambers and said drum, means for afio'rdmg a restricted communication between the other of said chambers and the outer air, said partition being movable in said casing by a difference in pressure upon theopposite sides thereof, means for normally returning -said partition to a determined position as the pressure upon the sides thereof becomes stable and equalized, a controller arm 'for said air. exhausting means, said arm having a tendency to move into a determined position, and mechanical connections between said" partition and said arm which permit the latter to be moved independently of said partition from its'normal position substantially to the limit .of its travel, saidpa'rtition and mechanical connections adapted to enact to govern the return of said arm to its determined position.

3. In an automatic pressure controller, the

"combination ofa drum, means for exhaustmg all from sald drum, a controller arm for sald air exhausting means, said arm having atendency to move mt-o a determlned posit1on,.a' controlling member for sald arm,

'means for moving said member'substantiallg in accordance with the pressure in sai drum, means for impeding saidmovement of said member sufficiently to :prevent 1110- mentary fluctuations in pressure in said drum from displacing said member and for preventing. movement of said member at undue speed for changes in pressure other than mere momentary. ones, separable connectin 'means between said memb'er and arm, sai

arm adapted to be moved independently of;

*s'aid'me'mbenfrom said positionsubstantlally to the limit of; its travel, said member and connectingmeans adapted to oo-a'ct to govern the return of saidj a-rm tojsaid determined posit-ion thereof.

.In testimony whereof, I have signed mv name to this specification-in the rescnce- ?th' day- (if zonns'rnn s. nunmes witnesses, thisl Witnesses z".

A. .L. Mnssno, LOUIS G. BARTLETT. 

